-LRB- CNN -RRB- -- Saudi Arabia 's crown prince was convalescing Saturday in Morocco where he arrived this week after surgery for an undisclosed illness in New York City , the state-run Saudi Press Agency said .

Saudi Crown Prince Sultan bin Abdulaziz Al Saud , right , seen in a 2007 file photo

Crown Prince Sultan , who is also the nation 's deputy prime minister , completed `` all medical tests and treatments in the aftermath of the medical surgery he has previously undergone , '' the news agency said , quoting a statement from the Royal Court .

Sultan arrived in the Moroccan city of Agadir on Wednesday , the press agency said . Speculation about his health has been mounting since he arrived in New York in February .

While Saudi officials maintain publicly that Sultan 's health has improved , the appointment in late March of a second deputy prime minister has raised more questions about the extent of his illness .

Last month , Saudi Arabia 's King Abdullah issued a royal decree naming the interior minister , Prince Nayef -- the powerful brother of the crown prince and half-brother to the king -- to the post of second deputy prime minster . The appointment appears to mean Nayef is now the country 's crown prince in waiting and second in line to be king .

In recent weeks , local media have quoted Nayef as downplaying rumors that the crown prince may be seriously ill .

`` I would like to assure you that the crown prince 's health is very good , '' he told reporters in March , according to the English-language daily newspaper Arab News . `` God willing , after the medical vacation he will return to the kingdom in full health . ''

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Saudi Arabia 's crown prince convalesces in Morocco after surgery in New York

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Illness of Crown Prince Sultan bin Abdulaziz Al Saud was not revealed

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Appointment of second deputy prime minister raises questions about illness